Obama’s approval rating is 69 percent among Twitter users, according to a Wednesday Wall Street Journal/NBC News poll. The president’s Twitter approval rating is in stark contrast with his national approval rating of 43 percent as well as his 47 percent rating on Facebook.

However, the poll reveals that Twitter could well be rebranded as a playground for Obama’s base. More than one in 10 Twitter users (13 percent) self-identify as a liberal Democrat. Only 8 percent identify as a conservative and 6 percent self-identify as tea party conservatives.

This may be explained by the president’s expanding Twitter following.

In 2008, Obama, then an Illinois senator, drew a total of 118,107 followers to his campaign Twitter account compared to Sen. John McCain’s 4,942 followers, according to online statistics tool Trendrr. Obama’s page gained 10,000 followers between Nov. 3 and Nov. 4, 2008 (Election Day) alone.

Obama now has 11,526,492 followers on his account as of noon, Wednesday. He is also number six on Twitaholic’s Top 100 list of most followed tweeters.

Followers are Twitter users who sign up to receive another user’s tweets. Therefore, a message posted on the president’s campaign Twitter account reaches over 11 million users and possibly more if the message is retweeted or reposted on another person’s Twitter account.

Obama’s High Approval Ratings on Twitter

Obama has posted 2,309 messages or updates on his Twitter site thus far, 1,143 more updates than the most followed member of Twitter, Lady Gaga.

Obama’s influence has grown within Twitter to cultivate a liberal atmosphere. Outside of Twitter, a November Gallup poll shows evidence that Obama’s Democratic base has shrunk.

According to the poll, the percentage of Americans identifying as Democrats or leaning toward the Democratic Party since 2008 has fallen from 50 percent to 43 percent.

Democrats aged 30 to 49 have moved more to the right of the political spectrum in the past three years – more than any other age group. The percentage of middle-age adults who as a whole self-identify as Democrats has dropped from 38 percent to 34. Among those who previously considered themselves Democrats, three percent have changed their affiliation.

Nearly three-quarters (74 percent) of Twitter users are under the age of 44, according to 2010 data collected by the Digital Buzz blog. Twitter’s largest demographic are users between the ages 26 and 34 (30 percent).

Notably, Facebook’s largest age demographic, according to Digital Buzz, consists of an even younger cohort – users aged 18 to 25 (29 percent). Yet Obama’s approval rating among Facebook users is less than half.

The Gallup poll shows that most U.S. adults aged 18 to 29 have moved more to the left of the political spectrum (2 percent as a whole) in the past three years. At the same time, a Pew Research poll reveals that Obama enthusiasm is waning among that age group.

A November survey found that just 48 percent of young voters 18 to 29 years old said Obama makes them feel hopeful. In November 2008, 81 percent said the same.